The invention concerns a divided disk brake arrangement having a disk with braking surfaces and a disk holder which is non-rotatably connected to the disk brake and secured by a screw connection. The disk holder and the braking disk are mounted so that they can move relative to each other in the radial direction in order to compensate for thermal expansion differences.
Divided disk brake arrangements are known from motor sports and sports cars, and they use braking disks made of a highly heat-resistant and abrasion-resistant material such as a carbon fiber material, for example, while the disk holder is made from a light metal such as aluminum.
Since the materials of the disk and the disk holder have different coefficients of thermal expansion, and since in use the disk brake arrangement can be subjected to temperature fluctuations of several hundred degrees Celsius, the disk and the disk holder expand by different amounts. Such different thermal expansions require that the connection between disk holder and braking disk allow these two parts to expand relative to each other.
To permit such expansion, it is possible to secure the disk holder in floating manner on the braking disk, or to secure the braking disk in floating manner on the disk holder. Both of these known measures are illustrated in FIGS. 3A, 3B and 4.
FIGS. 3A and 3B show a known divided disk brake arrangement 1 that rotates about an axis of rotation A and floatingly mounts a disk holder 2 on a braking disk 3. Disk holder 2 has U-shaped radial recesses 4 arranged along its periphery. A radially movable slide bush 5 is inserted in each recess. A screw 6 extends through a borehole in slide bush 5 and a borehole in the braking disk 3 and is tightened against disk 3 with a nut 7. The slide bush 5 has a section 8 for disk holder 2 which is slightly wider than the thickness of the holder (in the cold state) to create free play 9 that permits axial expansion.
In the alternative known configuration illustrated in FIG. 4, a radially enlarged hole 4′ is provided in braking disk 3 that receives a slide bush 5′. In this solution, the relative radial movement between disk holder 2 and braking disk 3 is permitted by hole 4′ in brake 3. Here as well, section 8′ of the guide bush 5′ for disk brake 3 is slightly larger than the thickness of the disk in the region of hole 4′ (in the cold state), so that here as well a play 9′ is provided for axial thermal expansions.
The play permitting axial thermal expansions causes wear and tear during operation, since the play not only enables thermal expansions, but also leads to relative movements between guide bush 5 or 5′ and disk holder 2 or braking disk 3 at low temperatures.